62 



MISC. PUBLICATION 273, U. S. DEPT. OF AGRICULTURE 



MOST IMPORTANT PINE DEFOLIATORS 



The pine butterfly {Neophasia menapia Feld.) {31) is potentially 

 one of the most dangerous enemies of ponderosa pine in the North- 

 western States. One of the earliest recorded outbreaks occurred near 

 Spokane, Wash., in 1882. Since that date several outbreaks have 

 developed in the ponderosa pine stands of Oregon, Washington, 

 Idaho, and British Columbia. One of the worst of these occurred 



on the Yakima In- 

 dian Reservation in 

 Washington during 

 the period 1893-95. 

 Ponderosa pine over 

 a})proximately 150,- 

 000 acres av a s af- 

 fected and from 20 to 

 90 percent of the 

 stand killed over this 

 large area. The total 

 loss amounted t o 

 nearly a billion 

 board feet, and the 

 effects of this out- 

 break are still evi- 

 dent. A more recent 

 outbreak severely de- 

 foliated thousands of 

 acres of ponderosa 

 pine along the Little 

 Salmon and Payette 

 Eivers in Idaho in 

 1922 and 1923. Old, 

 mature ponderosa 

 pines are more sus- 

 ceptible to injur y 

 than t h e younger, 

 thriftier trees. West- 

 ern white pine and 

 lodgepole pine, when 

 in mixture with pon- 

 derosa pine, are also 

 attacked, and Doug- 

 las fir is reported to have been injured in outbreaks of the pine 

 butterfly along the coast of British Columbia. 



The adult (fig. 27) is a white butterfly with black markings and 

 a wing expanse of about 1% inches, resembling in general the 

 common cabbage butterfly. The wings of the male are pure white 

 except for some black markings on the tips. The forewings of the 

 female have similar black markings, but have a distinct yellowish 

 cast; the hind wings have the same yellowish cast but have a much 

 heavier black marking than in the male. With many females, but 

 not all, there are bright orange spots along the apical margin of the 

 hind wings. These butterflies may be seen nearly every year flying 

 about in ^iwQ and fir forests and hovering about the tops of trees. 



Figure 27. — The pine butterfly {Xeophasia menapia) : Eggs, 

 larvae, pupae, and adults, male above, female below. 

 Natural size. (Evenden.) 



